The present invention relates to a programmable time switch, and more particularly, the present invention relates to a programmable time switch which supplements a function of a timer for controlling operations of diverse electronic and electric instruments or equipment and by which a user can easily make reservations for times or time intervals, cancel such reservations, confirm reservations, and input the current time.
Generally, a timer has several operating modes as shown in FIG. 1. The operating modes of the timer include an A mode in which the timer is started at a current time and converted from an on-state to an off-state when a reserved time is reached or a reserved length of time is lapsed, a B mode in which the timer is started at the current time and converted from the off-state to the on-state when the reserved time is reached or the reserved length of time is lapsed, a C mode in which the timer is started from the off-state, is converted to the on-state for the reserved length of the time as the current time reaches the reserved time, and then is returned to the off-state, and a D mode in which the timer is started from the on-state, is converted to the off-state for the reserved length of time as the current time reaches the reserved time, and then is returned to the on-state.
In the timer having the operating modes described above, a number of time reservations can be easily set and simply confirmed.
Among timers of the prior art, a minute minder (timer) of a spiral spring type provides advantages in that it allows a desired time interval to be easily set from a current time. However, the minute minder of a spiral spring type has low precision in turning on/off equipment or an instrument at a precise time. Also, a mechanical programmable time switch of a quartz-vibrated type or a motor type provides advantages in that since a reserve pin is disposed in a shape of a circle and has 24 hour representations, a reserved time can be confirmed at a glance. However, since the mechanical programmable time switch is mechanically turned on or off, precision is deteriorated relying upon play between elements thereof. Also, since the reserve pin must be inserted by hand, it is difficult to reserve a minute unit which is smaller than 10 minutes or 15 minutes. Further, the mechanical programmable time switch has disadvantages in that the reserve pin must be disposed in the counterclockwise direction.
In addition, while an electronic timer of a figure arranging type has high precision to allow time reservations of a second unit, it takes too much time to set a reservation program, an input scheme is so complicated that it is apt to be forgotten whereby the reservations must be set while referring to a manual. Also, the reservations cannot be confirmed at a glance.
Further, another electronic timer of a circular crystal type provides advantages in that when a minimum segment is set to be larger than 20 minutes. However, in the electronic timer, it takes too much time to set the reservation at one minute or 5 minute units. For example, if one minute can be reserved into one segment and it takes on second, 10 seconds are need to reserve 10 minutes, 60 seconds are needed to reserve one hour, and 720 seconds (12 minutes) are needed to reserve 12 hours. For this reason, it takes too much time to set the reservations. Also, in the electronic timer, since a reserve mode or a release mode must be selected when one segment is passed upon reservation, a visual discrimination is made difficult.
Accordingly, the present invention has been made in an effort to solve the problems occurring in the prior art, and an object of the present invention is to provide a programmable time switch by which a number of time reservations are easily set and simply confirmed, whereby convenience of a user is enhanced.
In order to achieve the above object, according to the present invention, there is provided a programmable time switch comprising: a display for displaying a time or a time interval set by a user to be reserved, the display having a current time display part formed at a center portion thereof for displaying an hour hand and a minute hand which represent a current time, an hour unit display part formed at a middle portion thereof for displaying the reserved time or time interval in terms of hours, and a minute unit display part formed at an edge portion thereof for displaying the reserved time or time interval in terms of minutes; a current time display section, an AM/PM display section and a mode display section for digitally displaying the current time, the AM or PM and an operating mode of a timer, respectively; a set section having a plurality of buttons for setting, canceling or confirming the reserve time or time interval; a control section for controlling through a drive section a peripheral interface connected thereto in accordance with the reserved time or time interval set through the set section, and for displaying the reserved time or time interval through the display; a memory for providing a program and a work area which are necessary for controlling operation of the control section; a clock supply section for supplying a clock which is necessary for the controlling operation of the control section; and a switch for keeping the drive section turned on or off irrespective of a setting of the timer or for making the drive section operate the timer.